Do you think you're missing the person you thought he could be? Perhaps the family life you hoped for, if only you just kept trying (but you did keep trying, and the wish never came true.)
When you've left a very controlling partner, life can feel very sort of flat & rudderless for a while. It's because the controller made sure you were always thinking about him - what mustn't be wrong, what must be ready, how you must speak, what you must ask, what you mustn't mention, what he expects, just how he likes it, and on and on.
After it starts to sink in that you don't NEED to be anxious all the time, there's this odd little period when it feels like you don't know what to do! Nobody's telling you off, nobody's going to hit you or make your kids' lives a misery, you can DO WHAT YOU LIKE!!! But what is that?? 
I remember standing in the middle of a massive Sainsbury's, looking at the miles of shelves, feeling all at sea because I no longer had to buy what XH liked! I tried feeling excited, but actually it was unnerving ... I'd forgotten what I like to eat, and also what music I like.
They take up so much of your head space, freedom feels 'empty' in a way. One good thing to do with your new free time is write down how you want your future to look, and your DC's. Then you can make picture boards or write what needs to happen for this to come true - step by step. Try to do fun things as well! If you can't remember what you love doing, try out loads of new things and see what clicks.
You'll get through this, and come out stronger :)